Thank you for taking your time in taking interest to assist me with my issue. I am currently doing a project that is composed of several components: Arduino Nano (6-12V & 40mA), Bluetooth 2.1+EDR (3.3V & 25-30mA), and Gyroscope + Accelerometer (3V). What I am trying to figure out is find a battery that would be able to power all these devices without going out of the dimensions of 2"x2"x.5". Also the goal is to have the device to last at least 12 hours. Can any one suggest something that would be able to this? I am open to other recommendations.